Method and Device of Performing Multi-Radio Access Bearer Power Scaling

ABSTRACT

The present disclosure relates to a method and user equipment, UE, in a wireless communication network of performing power scaling on uplink transmission to a receiving radio access node, RAN. The disclosure particularly relates to a method and user equipment for power scaling on a multi-radio access bearer, multi-RAB, wherein a Dedicated Physical Data Channel, DPDCH, and an enhanced Dedicated Physical Data Channel, E-DPDCH are configured for uplink transmission from the UE to the receiving RAN. The method comprises determining a total UE transmit power exceeding a predetermined maximum power limit value. The total UE transmit power is reduced to the predetermined maximum power limit value by reducing one or more E-DPDCH gain factors by an equal scaling factor. A DPDCH transmission status is determined, whereupon a power scaling procedure is selected based on the determined DPDCH transmission status. The selected power scaling procedure is applied on the uplink transmission.

RELATED APPLICATIONS

This application claims priority as a continuation of U.S. applicationSer. No. 14/411,965 filed Dec. 30, 2014, which is a US National Stageapplication of PCT/SE2013/051256 filed Oct. 29, 2013, which claimsbenefit of U.S. Provisional Application No. 61/796,097 filed Nov. 2,2012.

TECHNICAL FIELD

The present disclosure relates to a method and user equipment. UE, in awireless communication network of performing power scaling on uplinktransmission to a receiving radio access node, RAN. In particular, thedisclosure relates to a method and user equipment for power scaling on amulti-radio access bearer, multi-RAB, wherein a Dedicated Physical DataChannel, DPDCH, and an enhanced Dedicated Physical Data Channel. E-DPDCHare configured for uplink transmission from the UE to the receiving RAN.

BACKGROUND

One example cellular communications system is Universal MobileTelecommunications Systems, UMTS. Wideband Code Division MultipleAccess. W-CDMA. Wireless communication systems following UMTStechnology, were developed as part of Third Generation, 3G, RadioSystems, and is maintained by the Third Generation Partnership Project,3GPP. A mobile radio communication system, such as a UMTS type system,includes a mobile radio communication network communicating withwireless devices, also known as mobile terminals or user equipments, UEsand with external networks. The UMTS network architecture includes aCore Network, CN, interconnected with a UMTS Terrestrial Radio AccessNetwork, UTRAN, via an Iu interface. The UTRAN is configured to providewireless telecommunication services to users through mobile radioterminals, referred to as user equipments. UEs, in the 3GPP standard,via a Uu radio interface. A commonly employed air interface defined inthe UMTS standard is W-CDMA. The UTRAN has one or more radio networkcontrollers, RNC, and base stations, referred to as Node Bs by 3GPP,which collectively provide for the geographic coverage for wirelesscommunications with UEs. Uplink. UL, communications refer totransmissions from UE to Node B, and downlink, DL, communications referto transmissions from Node B to UE. One or more Node Bs are connected toeach RNC via an Iub interface; RNCs within a UTRAN communicate via anIur interface. An example block diagram of an UMTS WCDMA is shown inFIG. 1.

Radio transmitters are generally limited in total transmit power, alimit imposed by regulatory agencies or by the battery or poweramplifier technology. This power limitation may result in reduced radiocoverage. For example, as user equipment, UE, moves away from its Node Bbase station, it typically increases its transmission power to maintainthe same level of quality at the base station. The UE output power iscontrolled by the Node B base station via one or more power controlloops. When the UE reaches a maximum power and may no longer increaseits power to maintain the signal quality desired at the base station,power scaling is applied. This may occur for example when the UE isclose to cell-edge, or when the UE enters a region of deep signal fade.

Mobile networks with High Speed Packet Access, HSPA, include High SpeedDownlink Packet Access. HSDPA, and High Speed Uplink Packet Access.HSUPA, or Enhanced Uplink, EUL. The enhanced uplink introduces two newcode-multiplexed uplink physical channels: an enhanced data channel,E-DCH Dedicated Physical Data Channel, E-DPDCH, and an enhanced controlchannel, E-CCH Dedicated Physical Control Channel. E-DPCCH. In EUL, theDedicated Physical Control Channel, DPCCH, carries pilot, power control,and Inner Loop Power Control, ILPC, information. The transport format ofEUL is designated as E-DCH Transport Format Combination, E-TFC. Astandard E-TFC table is set forth in 3GPP specification 25.321. Atransmit power gain factor named βed is used to indicate the enhanceddata channel E-DPDCH amplitude for each E-TFC in the table, and atransmit power gain factor named βec is used to indicate the amplitudeof E-DPCCH. The power level of the DPDCH is indicated by βd for eachtransport format, and the parameter βc is used to indicate the DPCCHtransmit power level. A predetermined small minimum transmit power levelof E-DPDCH is specified using βed, min in the 3GPP specification 25.214.In the uplink, DPCCH is used as a power reference with the power offsetof all the other physical channels being defined relative to the DPCCHpower.

A configurable transmit power gain factor βed, min avoids excessive down

scaling of the data channel E-DCH power by setting a minimum power levelfor the E-DCH. The configurable βed, min permits a better trade-off ofthe power allocation between the E-DCH and the DPCCH control channelduring UE power limitation, which in turn improves the EUL coverage.FIG. 2 illustrates power allocated for E-DCH with and without aconfigurable βed, min.

TS 25.214. “Physical layer procedures (FDD)”, ver. 11.3.0, 2012-09-19,describes current 3GPP power scaling. In subsection 5.1.2.6, powerscaling handling when a UE is power limited is described. Subsection5.1.2.6 sets forth different power scaling procedures which are applieddepending on if DPDCH is configured or not, and if E-DCH configured ornot. Here, the term “configured” means that physical channel radioresources are reserved for transmission. The configuration when E-DCH isnot configured and DPDCH is configured is from now on referred to asconfiguration 1. The configuration when E-DCH is configured and DPDCH isnot configured is from now on referred to as configuration 2. Theconfiguration when both E-DCH and DPDCH are configured is from now onreferred to as configuration 3. To say that E-DCH is configured meansthat one or more E-DPDCH(s) physical channel resources are reserved foruplink transmission from user equipment, UE, to NodeB. Similarly, to saythat DPDCH is configured means that one or more DPDCH(s) physicalchannel resources are reserved for transmission from user equipment. UE,to NodeB.

In the power scaling applied for configuration 1, the power scalingprocedures inform the UE, after applying DPCCH power adjustments andgain factors, to apply additional scaling to the total transmit power sothat it is equal to the maximum allowed power. DPCCH/DPDCH andDPCCH/HS-DPCCH power ratios are maintained.

In the power scaling applied for configurations 2 and 3 where E-DCH isconfigured, the user equipment, UE, after applying DPCCH poweradjustments and gain factors, first reduces all the E-DPDCH gain factorsβed,k by an equal scaling factor to respective values βed,k,reduced sothat the total transmit power is equal to the maximum allowed power.Then, power scaling procedures differ depending on whether a DPDCH isconfigured. In the power scaling applied for configuration 2, whereDPDCH is not configured, the power scaling follows a procedure which,depending on a network

-configurable transmit power gain factor βed,min sets a limit on howmuch the user equipment may scale down the E-DPDCH gain factors βed,k.At this point, if the user equipment. UE, transmit power still exceedsthe maximum allowed transmit power limit, equal scaling is applied toall channels, similar to what is done for the power scaling applied forconfiguration 1. This procedure gives the network control over arelative lower bound of the E

IDPDCH gain factors βed,k and in turn improves the EUL coverage asdescribed above.

In power scaling applied for configuration 3 where DPDCH also isconfigured, the power scaling procedure allows downscaling of E-DPDCHgain factors βed,k,reduced down to the “smallest quantized βed,k value”(see the definition in TS 25.214. “Physical layer procedures (FDD)”,ver. 11.3.0, 2012-09-19). If βed,k,reduced is lower than the “smallestquantized βed,k value,” then discontinuous transmission, DTX, of theE-DPDCH(s) is(are) allowed. The DTX procedure secures performance ofDPDCH traffic over E-DCH traffic.

EP 1 931 160 A1 relates to a mobile station and communications method. Atransmit power control process carried out by the mobile station isdisclosed. When an estimated total transmit power is exceeds a Pmaxvalue, a gain factor of E-DPDCH is reduced so as to reduce the totaltransmit power. ‘Additional channel transmit power scaling’-regions aredisclosed where additional channel transmit power scaling is applied instates in which DPDCH data are transmitted.

However, the current 3GPP power downscaling procedures has a negativeimpact on DCH performance and causes un-due power scaling of E-DCHtraffic.

SUMMARY

The present disclosure relates to user equipment transmit power controland provides a more adequate multi-RAB power scaling configuration. Itis an object of the present disclosure to provide a method and userequipment that solves the problem of un-due power scaling of E-DCHtraffic transmitted in a multi-RAB configuration where a DedicatedPhysical Data Channel, DPDCH, is also configured. The disclosed methodenables an improved power scaling for multi-RAB.

The present disclosure presents a method in a user equipment. UE, in awireless communication network of performing power scaling on uplinktransmission to a receiving radio access node, RAN, on a multi-radioaccess bearer, multi-RAB. A Dedicated Physical Data Channel, DPDCH, andan enhanced Dedicated Physical Data Channel, E-DPDCH are configured foruplink transmission from the UE to the receiving RAN. The methodcomprises determining a total UE transmit power exceeding apredetermined maximum power limit value. The total UE transmit power isreduced to the predetermined maximum power limit value by reducing oneor more E-DPDCH gain factors by an equal scaling factor. A DPDCHtransmission status is determined, whereupon a power scaling procedureis selected based on the determined DPDCH transmission status. Theselected power scaling procedure is applied on the uplink transmission.

The disclosed method provides the advantage of enabling a moresituational correct power setting for multi-RAB. It is a significantadvantage of the disclosure that it provides a power scaling procedureadapted to a DPDCH transmission status; so selection of power scalingprocedure is based on the DPDCH transmission status.

According to an aspect of the disclosure, a first power scalingprocedure is selected when the DPDCH transmission status reveals thatdata is transmitted on the DPDCH. Consequently, the disclosed methodprovides the advantage of enabling selection of a power scalingprocedure specifically adapted to the situation when a DPDCH istransmitted.

According to a further aspect of the disclosure, a first power scalingprocedure is selected that complies with a legacy 3GPP power scalingprocedure used for power scaling when a DPDCH is configured. Reuse of alegacy power scaling procedure provides the advantage of astraight-forward and simple implementation of the disclosed method.

According to an aspect of the disclosure, a second power scalingprocedure is selected when the when the DPDCH transmission statusreveals that data is not transmitted on the DPDCH. In multi-RABsituations where both DPDCH and E-DPDCH are configured, but DPDCH is nottransmitted, it is a significant advantage to provide a power scalingprocedure adapted for only E-DPDCH traffic. Such a power scalingprocedure enables an improved E-DPDCH traffic coverage.

According to a further aspect of the disclosure, a second power scalingprocedure is selected that complies with a legacy 3GPP power scalingprocedure used for power scaling when a DPDCH is not configured. Reuseof a legacy power scaling procedure provides the advantage of astraight-forward and simple implementation of the disclosed method.

According to an aspect of the disclosure, the method is performed in auser equipment operative in a wideband code division multiple access.W-CDMA, Universal Mobile Telecommunications Systems, UMTS. It isadvantageous to implement the method in a user equipment operative inW-CDMA UMTS, since the W-CDMA UMTS provides legacy 3GPP power scalingprocedures applicable as the first or second power scaling procedure.

The present disclosure also presents a user equipment. UE, for awireless network, the UE being configured for performing power scalingon uplink transmission to a receiving radio access node. RAN, on amulti-radio access bearer, multi-RAB. A Dedicated Physical Data Channel,DPDCH, and an enhanced Dedicated Physical Data Channel E-DPDCH areconfigured for uplink transmission from the UE to the receiving RAN. TheUE comprises a radio transceiving circuitry and an enhanced uplink, EUL,processor. The EUL processor comprises a UE transmission powerdetermining entity configured to determine when a total UE transmitpower exceeds a predetermined maximum power limit value. A UE powerreduction entity is configured to reduce the total UE transmit power tothe predetermined maximum value by reducing one or more E-DPDCH gainfactors by an equal scaling factor. A DPDCH transmission status isdetermined in a DPDCH transmission determining entity, whereupon a powerscaling entity is configured to select a power scaling procedure basedon the determined DPDCH transmission. The power scaling entity is alsoconfigured to apply the selected power scaling procedure on uplinktransmission from the radio transceiving circuitry.

According to an aspect of the disclosure, the power scaling entity isconfigured to select a first power scaling procedure when the DPDCHtransmission status reveals that data is transmitted on the DPDCH.

According to a further aspect of the disclosure, the first power scalingprocedure complies with a legacy 3GPP power scaling procedure for powerscaling when a DPDCH is configured.

According to another aspect of the disclosure, the power scaling entityis configured to select a second power scaling procedure when the DPDCHtransmission status reveals that data is not transmitted on the DPDCH.

According to a further aspect, the second power scaling procedurecomplies with a legacy 3GPP power scaling procedure for power scalingwhen a DPDCH is not configured.

According to an aspect of the disclosure, the user equipment, UE, isoperative in a wideband code division multiple access. W-CDMA. UniversalMobile Telecommunications Systems. UMTS.

The present disclosure also relates to a computer program, comprisingcomputer readable code which, when run on user equipment, UE, causes theuser equipment to perform the method disclosed above and below.

With the above in mind, the object of the present disclosure is toovercome at least some of the disadvantages of known technology asdescribed above and below.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 schematically illustrates a Universal Mobile TelecommunicationsSystems, UMTS, network.

FIG. 2 illustrates power allocation for enhanced uplink. EUL.

FIG. 3 is a flow chart illustrating exemplary method steps forperforming multi-radio access bearer power scaling in a user equipment.

FIG. 4A is a flow chart illustrating a first power scaling procedure.

FIG. 4B is a flow chart illustrating a second power scaling procedure.

FIG. 5 is a block diagram schematically illustrating a user equipmentembodiment.

DETAILED DESCRIPTION

The following sets forth specific details, such as particularembodiments for purposes of explanation and not limitation. But it willbe appreciated by one skilled in the art that other embodiments may beemployed apart from these specific details. In some instances, detaileddescriptions of well-known methods, nodes, interfaces, circuits, anddevices are omitted so as not obscure the description with unnecessarydetail. Those skilled in the art will appreciate that the functionsdescribed may be implemented in one or more nodes using hardwarecircuitry (e.g., analog and/or discrete logic gates interconnected toperform a specialized function, ASICs, PLAs, etc.) and/or using softwareprograms and data in conjunction with one or more digitalmicroprocessors or general purpose computers. Nodes that communicateusing the air interface also have suitable radio communicationscircuitry. Moreover, the technology can additionally be considered to beembodied entirely within any form of computer-readable memory, such assolid-state memory, magnetic disk, or optical disk containing anappropriate set of computer instructions that would cause a processor tocarry out the techniques described herein.

Hardware implementation may include or encompass, without limitation,digital signal processor, DSP, hardware, a reduced instruction setprocessor, hardware (e.g., digital or analog) circuitry including butnot limited to application specific integrated circuits, ASIC, and/orfield programmable gate array(s), FPGA, and (where appropriate) statemachines capable of performing such functions.

In terms of computer implementation, a computer is generally understoodto comprise one or more processors or one or more controllers, and theterms computer, processor, and controller may be employedinterchangeably. When provided by a computer, processor, or controller,the functions may be provided by a single dedicated computer orprocessor or controller, by a single shared computer or processor orcontroller, or by a plurality of individual computers or processors orcontrollers, some of which may be shared or distributed. Moreover, theterm “processor” or “controller” also refers to other hardware capableof performing such functions and/or executing software, such as theexample hardware recited above.

Although the description is given for user equipment, UE, it should beunderstood by the person skilled in the art that UE is a non-limitingterm comprising any wireless device or node equipped with a radiointerface allowing for at least one of: transmitting signals in theuplink, UL, and receiving and/or measuring signals in the downlink. DL.Some examples of UE in its most general sense are a PDA, laptop, mobile,sensor, fixed relay, mobile relay, and a radio network node, e.g. asmall base station using the terminal technology.

FIG. 1 illustrates an example block diagram of UMTS networkarchitecture. The network architecture includes a Core Network 10, CN,interconnected with a UMTS Terrestrial Radio Access Network 20, UTRAN,via an Iu interface. The UTRAN 20 is configured to provide wirelesstelecommunication services to users through mobile radio terminals,referred to as user equipments 30, UEs, in the 3GPP standard, via a Uuradio interface. A commonly employed air interface defined in the UMTSstandard is W-CDMA. The UTRAN has one or more radio network controllers21. RNC, and base stations 22, referred to as Node Bs by 3GPP, whichcollectively provide for the geographic coverage for wirelesscommunications with UEs 30. Uplink, UL, communications refer totransmissions from UE to Node B, and downlink. DL, communications referto transmissions from Node B to UE. One or more Node Bs 22 are connectedto each RNC 21 via an Iub interface; RNCs within a UTRAN communicate viaan Iur interface. The technology in this disclosure relates to the radiointerface Uu between a NodeB 22, and a UE 30.

As previously discussed, the UE radio transmitters are limited in totaltransmit power. As a UE 30 moves away from a Node B 22 to which the UEis attached, it increases its transmission to maintain the same level ofquality at the base station. The UE 30 output power is controlled by theNodeB 22. When the UE 30 reaches a maximum power and no longer has theability to increase its power to maintain the signal quality desired atthe base station, power scaling is applied. Exemplary situations of suchpower scaling include the situation when a UE 30 is close to a cell edgeor when the UE 30 reaches a region of deep signal fade.

FIG. 2 illustrates power allocation for Enhanced Uplink, EUL, in amobile network with High Speed Packet Access. HSPA. Power scaling forE-DCH with a configurable βed. min is illustrated on the right-handside. EUL introduced two new code-multiplexed uplink physical channels:an enhanced Data Channel, E-DCH, enhanced Dedicated Physical DataChannel, E-DPDCH and an enhanced Control Channel, E-DCH, enhancedDedicated Physical Control Channel. E-DPCCH. In EUL, the DedicatedPhysical Control Channel, DPCCH carries pilot, power control and InnerLoop Power Control (ILPC) information. A transmit power gain factornamed βed is used to indicate the enhanced data channel E-DPDCHamplitude for each E-DCH transport format combination. A transmit powergain factor βec is used to indicate the amplitude of E-DPCCH. The powerlevel of DPDCH is indicated by βd for each transport format and theparameter βc is used to indicate the DPCCH transmit power level. In the3GPP specification 25.214, a predetermined minimum transmit power levelof E-DPDCH is specified as βed,min. In the uplink. DPCCH is used as apower reference with the power offset of all the other physical channelsbeing defined relative to the DPCCH power. The use of a configurabletransmit power gain factor βed. min avoids excessive downscaling of thedata channel E-DCH power. The configurable βed. min permits a bettertrade of between the power allocation between the E-DCH and DPCCHcontrol channel during UE power limitation/scaling. The 3GPPspecification 25.214 “Physical layer procedures (FDD)”, ver. 11.3.0,2012-09-19 describes legacy 3GPP power scaling in detail. Subsection5.1.2.6 discloses power scaling procedures that are applied depending onif DPDCH is configured or not, and if E-DCH is configured or not. Theterm configured here applies to the situation where physical channelradio resources have been reserved for transmission. These legacy powerscaling procedures will be described below with reference to FIGS. 4aand 4 b.

FIG. 3 discloses a flow chart illustrating exemplary method steps forperforming multi-radio access bearer power scaling in a user equipment,UE. The user equipment is configured to perform the power scaling methodsteps for uplink transmission to a receiving radio access node,RAN/UTRAN, in a wireless communication network on a multi-radio accessbearer, multi-RAB. The disclosed power scaling procedure is applicablewhen E-DCH is configured; thus for Enhanced Uplink, EUL, in a mobilenetwork with High Speed Packet Access, HSPA. A Dedicated Physical DataChannel, DPDCH, and an enhanced Dedicated Physical Data Channel. E-DPDCHare configured for uplink transmission from the UE to the receiving RAN.

In a first step S31, the UE determines that the total UE transmit powerexceeds a predetermined maximum power limit value. The total UE transmitpower level is an instantaneous level where the UE transmit power of allchannels together exceeds a limit, over e.g. a slot that is a period of0.67 ms). The instantaneous level is defined in current 3GPPspecifications, e.g. the referenced 3GPP 25.214 specification. Thedetermining in the UE follows on receipt of power control informationfrom the NodeB, instructing the UE that power control must be exercised.This is part of legacy procedures, e.g as described in the referenced3GPP specification 25.214, and will not be discussed herein.

In a first power reduction step S32, the UE reduces total UE transmitpower to the predetermined maximum power limit value. Reduction of totalUE transmit power includes applying DPCCH power adjustments and gainfactors. Subsequently, the UE reduces all the E-DPDCH gain factors βed,kby an equal scaling factor to respective values βed,k, reduced so thatthe total UE transmit power is equal to the maximum allowed power. A UEDPDCH transmission status is determined in step S33 whereupon selectionS34 of a power scaling procedure is based on the determined DPDCHtransmission status. Following selection of a power scaling procedure,power scaling according to the procedure is applied to the uplinktransmission.

Selection of the power scaling procedure differs depending on whether aDPDCH is transmitted or not, i.e. if data is transmitted on theconfigured DPDCH. A first power scaling procedure is applied when theDPDCH transmission status reveals that a DPDCH is transmitted, while asecond power scaling procedure is selected when the DPDCH transmissionstatus reveals that a DPDCH is not transmitted, i.e. if the channel issimply allocated without sending data.

Legacy power scaling procedures are applicable for the selection of thefirst and second power scaling procedures. With a selection of legacyprocedures, the disclosure provides a very straight-forwardimplementation while still offering significant advantages in that itenables a more situational correct power setting for multi-RAB. Hence,if data is transmitted on the DPDCH the power scaling procedurecorresponding to a DPDCH being configured is executed and vice versa.

In the power scaling applied for the transmission status where DPDCH istransmitted, the power scaling follows a procedure which, depending on anetwork-configurable transmit power gain factor βed. min sets a limit onhow much the UE scales down the E-DPDCH gain factors βed,k.

In the power scaling applied for the transmission status where DPDCH isnot transmitted, the power scaling procedure allows downscaling ofE-DPDCH gain factors βed,k reduced down to the “smallest quantized βed,kvalue” according to the definition in TS 25.214 “Physical layerprocedures (FDD)”, ver. 11.3.0, 2012-09-19). If βed,k reduced is lowerthan the “smallest quantized βed,value” then discontinuous transmission,DTX, of the one or more E-DPDCH is allowed. The DTX procedure securesperformance of DPDCH traffic over E-DCH traffic.

The power scaling procedures illustrated in FIGS. 4a and 4b correspondto procedures presented in 3GPP standard TS 25.214 and in particular insection 5.1.2.6 disclosing the conditions for applying or not applyingpower scaling for E-DCH only transmissions.

FIG. 4a illustrates the power scaling procedure applicable when an E-DCHis configured and a DPDCH is transmitted. The illustrated power scalingprocedure represents an exemplary first power scaling procedure asmentioned above. In a first step S411, an evaluation is performed if anyβed,k,reduced/βc is less than the smallest quantized βed,k value in oneor more βed,k tables (e.g table 1B.2 as defined in said 3GPP standard TS25.214). In a subsequent step S412, DTX is used on the E-DPDCH, when theevaluation in S411 provides the result that βed,k,reduced/βc is lessthan the smallest quantized βed,k value. Consequently if not DTXed,βed,k is consequently quantized in step S413 to closet lower βed,k valueaccording to the one or more βed,k tables. The table used forβed,k,reduced quantization is dependent on if E-TFCI is greater thanE-TFCI ec, boost or not. When the UE transmit power in step S414 isfound to still exceed the maximum allowed transmit power, even thoughDTX is used on all E-DPDCHs, the first power scaling procedure involvesthe UE applying additional scaling to the total transmit power so thatit is equal to the maximum allowed power while maintaining the powerratio between DPCCH and DPDCH, between DPCCH and HS-DPCCH, between DPCCHand E-DPCCH, and between DPCCH and E-DPDCH as illustrated in step S43.

FIG. 4b illustrates the power scaling procedure applicable when an E-DCHis configured and a DPDCH is not transmitted. The illustrated powerscaling procedure represents an exemplary second power scaling procedureas mentioned above. In a first step S421, an evaluation is performed ifany βed,k reduced is less than any βed,k,reduced,min/βc regardless ofmodulation. If that is the case, βed,k is set to βed,k,min so thatβed,k,min/βc equals the minimum value of βed,k,reduced,min/βc andβed,k,original/βc where βed,k, original denotes the E-DPDCH gain factorbefore reduction and βed,k,reduced,min is configurable by higher layersin step S422. When βed,k is not set to βed,k,min; βed,k is consequentlyquantized in step S423 to closet lower βed,k value according to the oneor more βed,k tables. The table used for βed,k, reduced quantization isdependent on if E-TFCI is greater than E-TFCI ec, boost or not. When theUE transmit power in step S424 is found to still exceed the maximumallowed transmit power, even though βed,k,reduced equals βed,k, min forall values of k, the second power scaling procedure involves the UEapplying additional scaling to the total transmit power so that it isequal to the maximum allowed power while maintaining the power ratiobetween DPCCH and DPDCH, between DPCCH and HS-DPCCH, between DPCCH andE-DPCCH, and between DPCCH and E-DPDCH as illustrated in step S43, i.e.,the additional power scaling previously disclosed for the first powerscaling procedure of FIG. 4 a.

FIG. 5 shows a non-limiting exemplary block diagram of a user equipment50, the UE being configured for performing power scaling on uplinktransmission to a receiving radio access node RAN/UTRAN, on amulti-radio access bearer, multi-RAB. A Dedicated Physical Data Channel,DPDCH, and an enhanced Dedicated Physical Data Channel E-DPDCH areconfigured for uplink transmission from the UE to the receiving RAN. Theuser equipment 50 comprises a radio transceiving circuitry 51 and anenhanced uplink. EUL processor 52. A UE transmission power determiningentity 521 in the EUL processor is configured to determine when a totalUE transmit power exceeds a predetermined maximum power limit value. TheEUL processor further comprises a UE power reduction entity 522configured to reduce the total UE transmit power to the predeterminedmaximum value by reducing one or more E-DPDCH gain factors by an equalscaling factor. A DPDCH transmission determining entity 523 in the EULprocessor is configured to determine a DPDCH transmission status; and, apower scaling entity 524 is configured to select a power scalingprocedure based on the determined DPDCH transmission and to apply theselected power scaling procedure. The EUL processor also comprises theone or more βed,k tables used in the performance of the power scalingprocedures as described with reference to FIGS. 4a and b.

The above technology has been presented with reference to animplementation in the 3GPP standard TS 25.214, “Physical layerprocedures (FDD)”, ver. 11.3.0 2012-09-19. However, the disclosure isnot limited to such an implementation; any implementation covered by theclaim language is intended to fall within the scope of the disclosure.

Although the description above contains many specifics, they should notbe construed as limiting but as merely providing illustrations of somepresently preferred example embodiments. For example, non-limiting,example embodiments of the technology were described in a WCDMA UMTScontext. But the principles of the technology described may also beapplied to other radio access technologies. Indeed, the technology fullyencompasses other embodiments which may become apparent to those skilledin the art. Reference to an element in the singular is not intended tomean “one and only one” unless explicitly so stated, but rather “one ormore.” None of the above description should be read as implying that anyparticular element, step, range, or function is essential.

What is claimed is:
 1. A method in a user equipment, UE, in a wirelesscommunication network of performing power scaling on uplink transmissionto a receiving radio access node, RAN, on a multi-radio access bearer,multi-RAB, wherein a Dedicated Physical Data Channel, DPDCH, and anenhanced Dedicated Physical Data Channel, E-DPDCH are configured foruplink transmission from the UE to the receiving RAN, comprising:determining a total UE transmit power exceeding a predetermined maximumpower limit value; reducing total UE transmit power to the predeterminedmaximum power limit value by reducing one or more E-DPDCH gain factorsby an equal scaling factor; determining a DPDCH transmission status;selecting a power scaling procedure based on the determined DPDCHtransmission status; and applying the selected power scaling procedureon the uplink transmission.
 2. The method of claim 1, wherein a firstpower scaling procedure is selected when the DPDCH transmission statusreveals that data is transmitted on the DPDCH.
 3. The method of claim 2,wherein the first power scaling procedure complies with a legacy 3GPPpower scaling procedure for power scaling when a DPDCH is configured. 4.The method of claim 1, wherein a second power scaling procedure isselected when the step of determining DPDCH transmission status revealsthat data is not transmitted on the DPDCH.
 5. The method of claim 4,wherein the second power scaling procedure complies with a legacy 3GPPpower scaling procedure for power scaling when a DPDCH is notconfigured.
 6. The method of claim 1, wherein the wireless communicationnetwork is Universal Mobile Telecommunications Systems, UMTS, widebandcode division multiple access, W-CDMA.
 7. A user equipment, UE, for awireless communication network, the UE being configured for performingpower scaling on uplink transmission to a receiving radio access node,RAN, on a multi-radio access bearer, multi-RAB, wherein a DedicatedPhysical Data Channel, DPDCH, and an enhanced Dedicated Physical DataChannel E-DPDCH are configured for uplink transmission from the UE tothe receiving RAN, the UE comprising: radio transceiving circuitry; andan enhanced uplink, EUL, processor comprising a UE transmission powerdetermining entity configured to determine when a total UE transmitpower exceeds a predetermined maximum power limit value, a UE powerreduction entity configured to reduce the total UE transmit power to thepredetermined maximum value by reducing one or more E-DPDCH gain factorsby an equal scaling factor, a DPDCH transmission determining entityconfigured to determine a DPDCH transmission status; and, a powerscaling entity configured to select a power scaling procedure based onthe determined DPDCH transmission status and to apply the selected powerscaling procedure on uplink transmission from the radio transceivingcircuitry.
 8. The user equipment, UE, of claim 7, wherein the powerscaling entity is configured to select a first power scaling procedurewhen the DPDCH transmission status reveals that data is transmitted onthe DPDCH.
 9. The user equipment, UE, of claim 8, wherein the firstpower scaling procedure complies with a legacy 3GPP power scalingprocedure for power scaling when a DPDCH is configured.
 10. The userequipment, UE, of claim 7, wherein the power scaling entity isconfigured to select a second power scaling procedure when the DPDCHtransmission status reveals that data is not transmitted on the DPDCH.11. The user equipment, UE, of claim 10, wherein the second powerscaling procedure complies with a legacy 3GPP power scaling procedurefor power scaling when a DPDCH is not configured.
 12. The userequipment, UE, of claim 7, wherein the wireless communication network isUniversal Mobile Telecommunications Systems, UMTS, wideband codedivision multiple access, W-CDMA.
 13. A non-transitory computer-readablemedium storing a computer program comprising program instructions that,when executed processing circuitry in a user equipment, UE, configuresthe UE, with respect to operation in a wireless communication network,perform power scaling on an uplink transmission to a receiving radioaccess node, RAN, on a multi-radio access bearer, multi-RAB, wherein aDedicated Physical Data Channel, DPDCH, and an enhanced DedicatedPhysical Data Channel, E-DPDCH are configured for uplink transmissionfrom the UE to the receiving RAN, said computer program comprisingprogram instructions configuring the UE to: determine a total UEtransmit power exceeding a predetermined maximum power limit value;reduce total UE transmit power to the predetermined maximum power limitvalue by reducing one or more E-DPDCH gain factors by an equal scalingfactor; determine a DPDCH transmission status; select a power scalingprocedure based on the determined DPDCH transmission status; and applythe selected power scaling procedure on the uplink transmission.